Electric permutation lock arrangement

ABSTRACT

A permutation mechanism for a lock arrangement which avoids detection by stethoscope or other mechanical or electrical means. A set of multicontact rotary switches takes the place of conventional tumblers. When arranged in the correct sequence, a current path is established through the switches, which path becomes completely conductive upon the activation of an &#39;&#39;&#39;&#39;unlocking&#39;&#39;&#39;&#39; push-button switch. The push-button switch however, cannot be activated until the rotary switches are in proper sequence, and thus no detectable current flow can exist until the unlocking push-button is activated.

United States Patent [1 1 Ford et al.

[ 1 Sept. 18, 1973 1 ELECTRIC PERMUTATION LOCK ARRANGEMENT Inventors: Robert Brough Ford, Richmond;

Martin Herbert Lloyd, Addington, both of England International Standard Electric Corporation, New York, NY.

Filed: Oct. 27, 1970 Appl. No.: 84,391

Assignee:

[30] Foreign Application Priority Data Nov. 25, 1969 Great Britain 57,600/69 US. Cl. 200/43 Int. Cl. .i H0111 27/10 Field of Search "200/43, 45; 317/134;

References Cited UNITED STATES PATENTS 6/1922 Rayner 200/43 Primary ExaminerHerman J. Hohauser Attorney-C. Cornell Remsen, Jr, Walter J. Baum, Paul W. 'Hemminger, Charles L. Johnson, Jr., Philip M. Bolton, Isidore Togut, Edward Goldberg and Menotti J. Lombardi, Jr.

[57] ABSTRACT A permutation mechanism for a lock arrangement which avoids detection by stethoscope or other mechanical or electrical means. A set of multicontact rotary switches takes the place of conventional tumblers. When arranged in the correct sequence, a current path is established through the switches, which path becomes completely conductive upon the activation of an unlocking push-button switch. The push-button switch however, cannot be activated until the rotary switches are in proper sequence, and thus no detectable current flow can exist until the unlocking pushbutton is activated.

6 Claims, 7 Drawing Figures PATENTED SEP! 8 I975 sum-2 or 4 l I P I "b D/b/I/hg O Switches 0 MW n 800 M m u 2 m. .7 1 1 Inventors ROBE R T 8. FORD MAR TIN H, LLO YD Agent ELECTRIC PERMUTATION LOCK ARRANGEMENT BACKGROUND OF THE INVENTION The invention relates to a permutation mechanism for the electrical control of locks. The permutation mechanism may be mechanically coupled to a lock mechanism so as to withdraw a bolt or the like when the correct combination has been set up, or it may be situated remote from the lock mechanism.

A known form of permutation lock for safes contains a set of tumblers each of which must be set to a predetermined position by movement of a control knob so as to align a set of gates and allow a fence to drop, after which further rotation of the control knob will withdraw the bolt. In one class of such permutation locks each tumbler is provided by a vane, tab or the equivalent by means of which it may be rotated in either di rection by an overlapping vane or tab on an adjacent tumbler but may be left in any arbitrary position on reversal of the direction of rotation of the adjacent tumbler until that adjacenttumbler has been moved in the reverse direction through almost a complete revolution. To open the safe door, the control knob or dial is rotated a sufficient number of times in one direction as to entrain all the tumblers and then it is rotated first in one direction and then in the other to a sequence of angular positions denoted by letters or numbers on the dial so as to leave one tumbler and then the next and so on in their correct angular relationships for all the gates to be aligned.

SUMMARY OF THE INVENTION The present invention operates in similar manner insofar as the setting-up procedure is concerned, but instead of a mechanical arrangement of gates and fence the setting-up operation completes respective portions of an electrical circuit through which current may be caused to flow to operate a solenoid controlling a lock mechanism only when the correct sequence of dial settings has been performed.

According to the present invention there is provided a permutation mechanism comprising a shaft rotatable by a control knob, a plurality of rotors rotatable by the shaft, each rotor carrying a wiper and being arranged to make connection through its wiper to a different one of a set of electrical contacts individual to that rotor when it is rotated to corresponding different angular positions, means for rotating each of the rotors into a respective preselected one of the said different angular positions by rotation of the control knob alternately in one direction and in the opposite direction to a given sequence of angular settings, a further pair of contacts, closed only when the angular position of the control knob lies within a given range, and an electric current path completed through the first mentioned contacts and the further pair of contacts only when each rotor is in its predetermined position and the control knob is positioned within the given range.

With the mechanism of the present invention it is not possible to detect by touch or hearing when any rotor is in its correct position as there is no flow of electrical current until the whole operation is concluded, so defeating any effort to determine the correct combination by magnetic detection means. The mechanism is simple to make with the aid of printed circuit boards with the switch plates each carrying a wiper track and one of the sets of electrical contacts arranged with a rotor mounted on the switch plate in similar manner to known types of multiposition switches. The further pair of contacts which have to be closed to complete the electrical circuit may consist of contacts in a pushbutton switch operable only when the shaft is in one po sition, or in some embodiments it may consist of a further rotor mounted on the shaft or of contacts operated by a cam mounted on the shaft. Completion of the electrical circuit may be arranged to energize a solenoid withdrawing a latch bolt or it may energize a solenoid to withdraw a locking plunger from a dead bolt which may be withdrawn either by further electrical solenoid means or, in one type of lock mechanism forming the subject matter of our copending application Ser. No. 84,390, filed Oct. 27, 1970, by a bolt driving member permanently coupled to the control knob and which is free to move at all times but is coupled to a dead bolt only when a locking plunger for the dead bolt is withdrawn.

BRIEF DESCRIPTIONOF THE DRAWINGS Embodiments of the invention will be described with reference to the accompanying drawings, in which:

FIG. 1 is a side view of one form of permutation mechanism according to the invention;

FIG. 2 is a plan view and FIG. 3 a cross-section through a switch plate and its rotor used in the assem bly of FIG. 1;

FIG. 4 illustrates the combination of a latch bolt and a permutation mechanism according to the present invention showing one possible electrical arrangement for the'construction illustrated in FIGS. 1 to 3;

FIG. 5 illustrates diagrammatically a combination of lock mechanism and permutation mechanism utilizing for the permutation mechanism a modification of that illustrated in FIGS. 1 to 3;

FIG. 6 illustrates a modification to the arrangement of FIG. 1 whereby a bolt may be withdrawn, after the correct combination has been set up, by further rotation of the control knob; and

FIG. 7 is a block diagram illustrating a security system which may be used with the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The permutation mechanism of FIGS. 1 to 3 is shown in FIG. 1 enclosed in a box 1 which may be let into or mounted behind a door not shown. A shaft 2 mounted in a bearing 3 fixed to a front plate 4 passes through an assembly of switch plates 5 and rotors 6 and carries a control knob 7 outside the box and a disc 8 within the box behind the assembly of switch plates and rotors, the disc 8 being secured to the spindle 2 by means of a spring clip arrangement 9. A push-button 10 is mounted below the control knob 7 on a shaft 11 arranged to slide in bearings 12 and press against a spring-loaded lever member 13. The member 13, which functions as a bell crank, is a plate in the shape of a right-angled triangle pivoted at 14 adjacent its rightangled corner with one of its adjacent sides contacted by the shaft 11 and the other arranged to operate a microswitch 5 when the disc 8, which is provided with a peripheral notch, is in a position in which the member 13 can enter the notch. The disc 8 is of transparent material and carries markings which are illuminated by a pair of small lamps 16 so as to be visible through a peep-hole 17 in the front of the box.

The switch plates are mounted one behind the other on rods 18. Each is of insulating material carrying, as a printed circuit board, a continuous wiper track 19 (FIG. 2) and a set of contacts 20 each having its own conducting path 21 taken to the edge of the switch plate. Connection to the wiper track 19 is similarly made to an edge of the plate as illustrated at 22.

Each switch plate has a central circular cut-out which serves for mounting a rotor 23 of insulating material which carries on one side a wiper arm 24 which bridges the wiper track 19 to any one of the set of contacts 20. The rotor also carries on one side a peg 25 and on the other side a tab 26 (FIG. 3) for engagement with the peg on the rotor behind it. The peg, is of metal, should be insulated, as for example by an insulating sleeve not shown. The rotor assembly is held in position on the switch plate by means of screws joining together a front and a back plate on which are mounted, respectively, the peg 25 and the tab 26 with a spring washer 27 keeping the wiper 24 pressed against the wiper track. At the left hand end of the assembly, as viewed in FIG. 1, the end rotor carries a somewhat longer peg 25' for engagement with a peg driving member 26' projecting from the spindle 2. At the other end of the assembly the tab 26 is omitted from the end rotor on which it serves no purpose. Each of the rotors is apertured at 28 with a clearance hole for passage of the shaft 2.

Though each rotor is free to rotate in response to pressure applied to either side of its peg 25, the pressure exerted by spring washer 27 is sufiicient to hold it in any angular position if no rotary pressure is applied. In the embodiment of FIG. 1 three switch plates and rotors are employed but as many may be included as desired, and each switch plate typically carries 26 contacts to correspond tothe letters of the alphabet. When the control knob 7 is rotated in either direction during the course of one revolution of the shaft 2 and control knob 7, the tab 26' will engage the peg 25' on one side or the other and cause the corresponding rotor to rotate with the control knob. On further rotation the tab 26 on this first rotor will engage the peg 25 on the next rotor and, on still further rotation, the tab on the second rotor will eventually engage the peg on the third and, in this embodiment, last rotor. Thus all the rotors are now entrained for rotation in one direction. If the control knob is now rotated in the opposite direction, the rotors will stay in position until the peg 25' on the first rotor is engaged on its opposite side by the tab 26 and continued rotation will pick up the second rotor, which may be carried round to any desired position short of its tab engaging the peg on the last rotor if it is desired to leave this last rotor in its former position. The direction of rotation of the control knob is reversed again and after nearly a complete revolution it will pick up the first rotor of the assembly, leaving the other two set and the first rotor may be set to any position before it engages with the second rotor again. Finally the rotation of the control knob may once more be reversed until the notch in the periphery of disc 8 is in position to allow operation of the push-button and microswitch 15.

One way in which the contacts and wiper tracks of the switch plates may be interconnected and the permutation mechanism used to operate a door-lock is illustrated'in FIG. 4. At the top of this drawing there is represented diagrammatically a section through a door 30 in which is mounted a latch-bolt 31 normally urged by a spring 32, when the door is closed, into an engagement socket 33 in the door-joint. The latch-bolt 31 is shown with the customary bevel 34 to slide over a lip 35 when the door is pushed to. To withdraw the latchbolt a solenoid 36 is provided, one terminal of the solenoid being shown earthed and the other connected to the electrical circuit shown in the lower part of the drawing and enclosed in the broken lines (to show that all the components therein are contained within the box 1). The three switch plates and their rotors are indicated as Rotor 1, Rotor 2 and Rotor 3, respectively, and are designated in the drawing as Dialling Switches. Although it is necessary for only one connection to be wired to a selected one of the multiple contacts on a rotor, for convenience in changing the combination there is provided for each rotor a Setting Switch labelled Select 1, Select 2 and Select 3 respectively. These setting switches, not shown in FIG. 1, are simple single wafer switches having the same number of contacts as the rotors and mounted on and accessible from the back of the box 1. Each contact a, b, y, z on each rotor is wired to the corresponding contact of its setting switch, while interconnection to other parts of the circuit is shown made from the wiper arms of the dialling switch and setting switch respectively. A battery 40 mounted within the box 1, but not shown in FIG. 1, has one terminal earthed and the other terminal connected through microswitch 15 to the wiper of setting switch Select 3. The wiper of Rotor 3 is connected to the wiper of Rotor 2 and the wiper of setting switch Select 1 2 is connected to the wiper of setting switch Select 1 while the wiper of Rotor 1 is connected to solenoid 36. It will be seen that current can flow through the solenoid 36 only when the wiper'of each rotor is making contact with the same contact as is the rotor of its own setting switch, but the switch 15 'must also be closed. Then and only then is the latch-bolt 31 withdrawn. Assuming the door closed, to open it the dial 7 must first be rotated in a prescribed direction a sufficient number of times for it to pick up all three rotors and then set in sequence by alternate clockwise and anticlockwise rotation to the preselected angular positions corresponding to the settings of the respective setting switches. Finally the knob 7 must be rotated back again to the point at which the notch on disc 8 will allow entry of the lever member 13 and permit operation of the switch 15 by pressing the push button 10.

An alternative type of lock mechanism is illustrated in FIG. 5 and, basically, forms the subject matter of our copending application Ser. No. 84,390, filed Oct. 27, 1970. This may be operated either remotely or in juxtaposition to the permutation mechanism of FIGS. 1 to 3 by slight modification of the permutation mechanism. The lock mechanism consists of a bolt 50, which will normally be a dead bolt, although it may be a latch-bolt urged into its socket '51 by means of a compression spring 52, a locking plunger 53, which enters into an aperture 54 in bolt 50 and locks it in its closed position, and a bolt driving member 55 which is normally free to move backwards and forwards as indicated by. the arrows 56 unless linked to the bolt 50 by means of a spring-loaded link pin 57 normally held inoperative by means of compression spring 58. The link pin 57 is provided with a platform 59 on which rides an arm 60 of a lever 61 whose other arm 62 bears down on a flange 63 projecting around locking plunger 53. The bolt 50, its driving member 55 and the plunger 53 are mounted on a door 64 by meansof bearing bushes 65, 66, 67 and 68 respectively, while the'lever 61 rotates about a pivot fixed to the door. A solenoid 69 is provided for withdrawing the plunger 53, which, at the same time, will cause lever arm 60 to depress link pin 57 into engage ment with an aperture 70 in the bolt driving member 55. For operation by remote control the bolt driving member may be urged forward to lock the door by means of a solenoid 71 and may be retracted by another solenoid 72. To ensure that in this case the bolt driving member is not left in some intermediate position, spring-loading means such as represented by a rocking lever 73 and tension spring 74 are provided. Instead of operating the bolt driving member by remote control, it may, if desired, be coupled directly to the control knob of the permutation mechanism of FIGS. 1 to 3 by mounting the disc 8 eccentrically on the shaft 2 of FIG. 1, the push-button and its associated lever member 13 being omitted, and surrounding the disc with a ring 77 connected to the bolt driving member 55. A cam 76 mounted on the shaft 2 is then arranged to close the switch 15. If manual control of the bolt driving member 55 is provided, the solenoids 71 and 72 are omitted.

Taking into consideration first of all the case of remote control of the lock mechanism of FIG. 5, a battery 78 having one terminal grounded is connected through switch with the remainder of the permutation mechanism of rotors and setting switches, similarly to the arrangement of FIG. 4 and represented in FIG. 5 by the block 79 labelled PERM. The output from 79 is taken on the one hand to the solenoid 69 for withdrawing the plunger 53 and in parallel therewith to a relay 80 which operates contacts 81 whose closure supplies current, when the permutation mechanism is properly set up and a switch 15 is closed, to boltwithdrawing solenoid 72. For locking the door, it being assumed that compression spring 52 is omitted, a locking switch 82 in series with a further switch 83, automatically closed only when the door is closed, is provided for energization of locking solenoid 71.

Assuming that the door is locked and it is wished to open it, the permutation mechanism 79, which may be located at any convenient place, is operated in similar manner to that described with reference to FIG. 4 except that the cam 76 replaces the push-button for switch 15. With the correct combination set up and switch 15 closed, current will flow to solenoid 69 and retract locking plunger 53. After a slight delay imposed by the delay in operation of relay 80 provided to prevent binding should the locking plunger not be fully withdrawn before the bolt has moved significantly solenoid 72 is operated and the bolt is withdrawn, the link pin 57 having entered the recess 70. To bolt the door again after it has been pushed to, the lock switch 82 is operated and, provided the door is closed so that switch 83 is also closed and the control knob 7 has been moved to allow switch 15 to open, the bolt driving member will move to the left, as viewed in the drawing, until the bolt 50enters its socket 51 and plunger 53 comes over aperture 54; compression spring 58 will then urge up platform 59 forcing the plunger into its locking aperture. If desired additional switch contacts may be arranged in association with lever 61 to prevent continuous flow of current through any of the solenoids 69, 71 or 72; when the bolt is withdrawn the plunger 53 rides over the bolt face and maintains the link pin 57 in connection between the bolt and its drive so that thereafter solenoids 69 and 72 need no longer be operated.

For manual retraction of the bolt50, when the correct combination has been set up and switch 15 closed by the final setting operation of the control knob 7, solenoid 69 withdraws plunger 53 and link pin 57 enters into recess and couples the bolt to its driving member. Rotation of the control knob will now withdraw the bolt, the dwell of cam 76 being arranged so that the.

switch 15 remains closed long enough for the bolt to have been retracted sufficiently to enable the plunger 53 to ride on the surface of the bolt. Thereafter current to the solenoid is cut off, but the plunger continues to ride on the bolt surface, and the lever 61 continues to keep the link pin 57 engaged with the bolt driving member, the lever arm 60 sliding along the platform 59 of the link pin. To lock the door, the control knob is rotated in the opposite direction. As discussed more fully in our aforementioned co-pending; application Ser. No. 84,390, filed Oct. 27, 1970, lost motion is provided in the mechanism, or restriction is imposed on the setting position of the last rotor of the permutation mechanism, to ensure that the solenoid 69 is switched off before the bolt 50 is fully shot. The link pin 57 is therefore held engaged with the bolt by the plunger 53 riding on the bolt surface until the plunger is able to drop into its aperture 54 and allow the link pin to disengage. The control knob can then be rotated further until the rotors are upset from their preselected positions. I

The invention permits incorporation of the permutation mechanism in a variety of different security arrangements. One such security arrangement is illus trated in FIG. 7. Here the permutation mechanism of FIGS. 1 to 3, with the provision of setting switches as in FIG. 4, is represented by the two block diagrams 85, marked DIAL, and containing the dialling switches of FIG. 4, and the block 86 labelled SETTING SWITCHES containing the setting switches of FIG. 4 connected to the dialling switches as there described. The setting switches, however, may be set either manually or by means of a timed programming unit 87 marked PROGRAMME. A pair of clocks 88 labelled CLOCK l and CLOCK 2 are provided in series between the dial setting switches of block and a bolt operating solenoid 89 whose operation may withdraw a bolt driving member on a remote door. The clocks may consist of simple pulse oscillators and counters arranged to close the circuit between the dialling switches and solenoid 89 during predetermined time intervals only. Two clocks are provided in case one of them should fail, so that it is always possible, at the correct time, to gain access to the area controlled by the security system. For this purpose the two clocks are shown as feeding into an OR-gate 90 whose output feeds the solenoid 89. Additionally, and provided both clocks are operating, outputs from them are provided to an AND-gate 91 which feeds the programming unit 87. It is thus possible to arrange that the combination needed to open the door in question is changed, say, from day-time to night-time, while'only those people knowing the correct combination for the particular time can gain access. FIG. 7 illustrates but one of the many security arrangements made possible by means of the present invention for priority access to an area only at specified times.

While the principles of the invention have been described in connection with specific apparatus, it is to be understood that this description is made only by way of example and not as a limitation to the scope of the invention as set forth in the accompanying claims.

We claim:

1. A permutation arrangement comprising: a shaft rotatable by a control knob; a plurality of rotors rotatable by the shaft, each rotor carrying a wiper and being arranged to make connection through its wiper to a different one of a set of electrical contacts individual to that rotor when it is rotated to crresponding different angular positions; means for rotating each of the rotors to a respective preselected one of said different angular positions by rotating the control knob in a given sequence of angular settings; switch-operated contact means providing a pair of contacts closeable only when the angular position of the control knob lies within a given range, including a switch and a switch actuator positioned relative to a further rotatable member mounted on the shaft, said switch being actuatable only when said further rotatable member is positioned to permit said actuator to engage said switch; and an electric current path completed through the firstmentioned contacts and said switch-operated contact means only when each rotor is in its predetermined position and the control knob is positioned within said given range.

2. The arrangement as claimed in claim 1 further comprising a plurality of switch plates of insulating material arranged one plate mounted behind the other, each switch plate carrying a wiper track and a said set of electrical contacts, wherein each rotor is mounted with its wiper arranged to bridge the wiper track and 'any one of the set of contacts on a corresponding one of the switch plates, each rotor carrying a driving peg by means of which it may be rotated; a tab mounted on the shaft and arranged to engage the driving peg on an end one of the rotors, first on one side and then on the other as the shaft is rotated first in one direction and then in the other; and a pluarality of further tabs, each of which is mounted on a respective one of the rotors and arranged for engagement with the driving peg of the next rotor in similar manner to the tab on the shaft, so that continuous rotation of the shaft in either direction causes first the end one and then each of the other rotors in turn to partake in the rotation.

3. The arrangement as claimed in claim 2 wherein each switch plate is apertured to receive and serve as a bearing for its rotor.

4. The arrangement as claimed in claim 2 wherein said further rotatable member is a disc having a peripheral notch, and said switch actuator is a lever member for closing said pair of contacts, the arrangement being such that said switch is actuatable only by said lever member entering into the notch of said disc.

5. The arrangement as claimed in claim 1 wherein each one of the electrical contacts in a set is connected to corresponding contacts on a setting switch in series with the electrical connections to the rotor, the arrangement being such that by alteration of the setting switch the preselected one of the said different angular positions may be altered.

6. The arrangement as claimed in claim 4 wherein said lever member comprises part of a push button actuating arrangement and is a pivotable triangularshaped piece positioned to be in operative engagement with a shaft-mounted push button. II! 

1. A permutation arrangement comprising: a shaft rotatable by a control knob; a plurality of rotors rotatable by the shaft, each rotor carrying a wiper and being arranged to make connection through its wiper to a different one of a set of electrical contacts individual to that rotor when it is rotated to crresponding different angular positions; means for rotating each of the rotors to a respective preselected one of said different angular positions by rotating the control knob in a given sequence of angular settings; switch-operated contact means providing a pair of contacts closeable only when the angular position of the control knob lies within a given range, including a switch and a switch actuator positioned relative to a further rotatable member mounted on the shaft, said switch being actuatable only when said further rotatable member is positioned to permit said actuator to engage said switch; and an electric current path completed through the first-mentioned contacts and said switch-operated contact means only when each rotor is in its predetermined position and the control knob is positioned within said given range.
 2. The arrangement as claimed in claim 1 further comprising a plurality of switch plates of insulating material arranged one plate mounted behind the other, each switch plate carrying a wiper track and a said set of electrical contacts, wherein each rotor is mounted with iTs wiper arranged to bridge the wiper track and any one of the set of contacts on a corresponding one of the switch plates, each rotor carrying a driving peg by means of which it may be rotated; a tab mounted on the shaft and arranged to engage the driving peg on an end one of the rotors, first on one side and then on the other as the shaft is rotated first in one direction and then in the other; and a pluarality of further tabs, each of which is mounted on a respective one of the rotors and arranged for engagement with the driving peg of the next rotor in similar manner to the tab on the shaft, so that continuous rotation of the shaft in either direction causes first the end one and then each of the other rotors in turn to partake in the rotation.
 3. The arrangement as claimed in claim 2 wherein each switch plate is apertured to receive and serve as a bearing for its rotor.
 4. The arrangement as claimed in claim 2 wherein said further rotatable member is a disc having a peripheral notch, and said switch actuator is a lever member for closing said pair of contacts, the arrangement being such that said switch is actuatable only by said lever member entering into the notch of said disc.
 5. The arrangement as claimed in claim 1 wherein each one of the electrical contacts in a set is connected to corresponding contacts on a setting switch in series with the electrical connections to the rotor, the arrangement being such that by alteration of the setting switch the preselected one of the said different angular positions may be altered.
 6. The arrangement as claimed in claim 4 wherein said lever member comprises part of a push button actuating arrangement and is a pivotable triangular-shaped piece positioned to be in operative engagement with a shaft-mounted push button. 